From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Graf Subject: Re: KVM guest crashes Date: Mon, 26 Jan 2009 17:33:35 +0100 Message-ID: <497DE5DF.1030803@suse.de> References: <4975F26D.707@suse.de> <49762F13.5040507@redhat.com> <4976D954.9070901@suse.de> <4976E54C.4080407@redhat.com> <4976EC92.4010109@redhat.com> <4978D73A.6080500@suse.de> <20090123223644.GA4031@amt.cnet> <497DDC71.3000608@suse.de> <20090126162135.GA4316@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Avi Kivity , "kvm@vger.kernel.org" , Joerg Roedel , Sheng Yang To: Marcelo Tosatti Return-path: Received: from ns2.suse.de ([195.135.220.15]:49423 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751262AbZAZQdh (ORCPT ); Mon, 26 Jan 2009 11:33:37 -0500 In-Reply-To: <20090126162135.GA4316@amt.cnet> Sender: kvm-owner@vger.kernel.org List-ID: Marcelo Tosatti wrote: > On Mon, Jan 26, 2009 at 04:53:21PM +0100, Alexander Graf wrote: > >>> There are a number of problems that can result in this error, and the >>> problems are possibly different between the in-kernel PIT and userspace >>> PIT emulation (note it also happens with in-kernel PIT, just much more >>> rarely now). You can use the no_timer_check kernel option to bypass it. >>> >>> >> Hm - that option disables the whole check, making it always fail. I >> haven't seen any way to actually disable the check, telling Linux things >> are OK :-(. >> > > Hum, the option makes timer_irq_works always return true. Works for me > with in-kernel PIT. > > What you see with "apic=debug no_timer_check" ? > It does work with "noapic" for me, but that means I'm using the old PIC (which isn't necessarily bad, right?). So I can at least work around the issue for us now. It still needs to be fixed nevertheless. with "apic=debug no_apic_timer" 2.6.27 does: Setting APIC routing to flat ..TIMER: vector=0x30 apic1=0 pin1=0 apic2=-1 pin2=-1 ..MP-BIOS bug: 8254 timer not connected to IO-APIC ...trying to set up timer (IRQ0) through the 8259A ... ..... (found apic 0 pin 0) ... ....... works. while 2.6.25 does: ..MP-BIOS bug: 8254 timer not connected to IO-APIC Kernel panic - not syncing: IO-APIC + timer doesn't work! Try using the 'noapic' kernel parameter